EFFECTS OF AEROSOLS LOADING IN THE ATMOSPHERE ON THE VISIBILITY CHANGES IN ILORIN, NIGERIA.

Monitoring of aerosol loading constitutes a major environmental challenge. In this paper, aerosols measurements at the University of Ilorin, Ilorin, Nigeria over a period of over ten years have been analyzed for their characteristics and effects on visibility. The measurements show that a coarse aerosol regime exists in Ilorin with an average size of about 0.32, resulting in a high level of atmospheric turbidity. The visibility records from the Nigerian Metrological Agency, NIMET, were compared with the calculated values from the measured aerosol optical thickness (AOT). The results show that visibility in January and December could be reduced to as low as 25% of its value in clear skies.